Researchers forecast on Thursday that lightning strikes will increase by about 50 percent by 2100 in the continental United States because thunderstorms will become more explosive in the coming decades thanks to a warming planet.

This increase could lead to more wildfires because lightning already triggers half of these blazes in the United States, the researchers said. Lightning also kills dozens of Americans annually, with that risk expected to rise.

Considering factors including precipitation levels, cloud buoyancy and warming air, the scientists predicted a 7 percent increase in the number of lightning strikes with each degree Fahrenheit global average temperature increase (12 percent for each degree Celsius).

The 11 different climate models used in the study pointed to an increase of 7 degrees Fahrenheit (4 degrees Celsius) between now and 2100.

"There are about 30 million strikes per year in the contiguous U.S. now. So, in 2100, we would expect about 45 million per year," said climate scientist David Romps of the University of California, Berkeley and the U.S. government's Lawrence Berkeley National Laboratory, who led the study published in the journal Science.

"For every two lightning strikes in 2000, there will be three lightning strikes in 2100," Romps added.

The researchers said rising temperatures breed lightning because the amount of water vapor in the atmosphere - the fuel for thunderstorms - increases exponentially as the air gets warmer.